Intuitionistic Fuzzy Approach for Outsourcing Provider Selection in a Refinery

In this study, an intuitionistic fuzzy multi-criteria decision making approach is used for selecting the most appropriate outsourcing service provider for an oil refining enterprise on the Balkan peninsula. An optimal outsourcing problem is formulated and an algorithm for selection the most eligible outsourcing service provider is proposed using the concept of index matrices (IMs), where the evaluations of outsourcing candidates against criteria formulated by several experts are intuitionistic fuzzy pairs. The proposed decision-making model takes into account the ratings of the experts and the weighting factors of the evaluation criteria according to their priorities for the outsourcing service. Due to complexity of outsourcing process, the real numbers are not enough to characterize evaluation objects. Fuzzy sets (FSs) of Zadeh use the single membership function to express the degree to which the element belongs to the fuzzy set. As a result, the FSs is unable to express non-membership and hesitation degrees. Since intuitionistic fuzzy sets (IFSs) of Atanassov consider the membership and non-membership degrees simultaneously, they are more flexible than the FSs in modeling with uncertainty. The originality of the paper comes from the proposed decision-making model and its application in an optimal intuitionistic fuzzy (IF) outsourcing problem of a refinery. The presented approach for selection the most suitable outsourcing service provider can be applied to problems with imprecise parameters and can be extended in order to obtain an optimal solution for other types of multidimensional outsoursing problems by using n-dimensional index matrices.